The human amygdala and pain: Evidence from neuroimaging

Abstract

The amygdala, a small deep brain structure involved in behavioral processing through interactions with other brain regions, has garnered increased attention in recent years in relation to pain processing. As pain is a multidimensional experience that encompasses physical sensation, affect, and cognition, the amygdala is well suited to play a part in this process. Multiple neuroimaging studies of pain in humans have reported activation in the amygdala. Here we summarize these studies by performing a coordinate-based meta-analysis within experimentally induced and clinical pain studies using an activation likelihood estimate analysis. The results are presented in relation to locations of peak activation within and outside of amygdala subregions. The majority of studies identified coordinates consistent with human amygdala cytoarchitecture indicating reproducibility in neuroanatomical labeling across labs, analysis methods, and imaging modalities. Differences were noted between healthy and clinical pain studies: in clinical pain studies, peak activation was located in the laterobasal region, suggestive of the cognitive-affective overlay present among individuals suffering from chronic pain; while the less understood superficial region of the amygdala was prominent among experimental pain studies. Taken together, these findings suggest several important directions for further research exploring the amygdala's role in pain processing.

Activation of GPR30 attenuates chronic pain-related anxiety in ovariectomized mice

“…Chronic pain is an ideal model used to understand these types of conditions in the context of localized and integrated neural networks. The brain regions implicated in chronic pain and anxiety include somatosensory cortex, anterior cingulate cortex, prefrontal cortex, and amygdala (Apkarian et al, 2004;Lee and Tracey, 2013;Simons et al, 2014aSimons et al, , 2014b. Emotional disorder and pain possibly share the same biological pathways and neurotransmitters, which influence concurrent treatments (Blier and Abbott, 2001).…”

Naproxen Effects on Brain Response to Painful Pressure Stimulation in Patients with Knee Osteoarthritis: A Double-blind, Randomized, Placebo-controlled, Single-dose Study

“…The amygdala is indeed a relevant element in the processing of pain, but its activation is highly variable in pain experiments 36 . Only a small proportion of previous imaging studies have reported significant changes in the amygdala, which involved both signal increases and decreases according to a recent metaanalysis 36 . Thus, the finding of no net amygdala activation during pain provocation in our study is not an unexpected finding.…”

Pain-related autonomic response is modulated by the medial prefrontal cortex: An ECG–fMRI study in men

“…Based on previous studies, nine brain areas (regions involved in pain processing and being part of the CAN) were initially considered as ROIs: left and right insula, left and right thalamus, left and right medial prefrontal cortex (MPFC), anterior division of cingulate gyrus, amygdala and hypothalamus [5,11,22,31,36,37,47]. However, our group-level analysis in the present study, showed no significant pain-related activity in the amygdala or hypothalamus (see the Results section).…”